In case of performing writing by a mechanical pencil, the length of a lead projected from the end of a lead guide is limited to a substantially predetermined amount beyond which the lead is liable to be broken, and when the length of such projection is reduced due to the wear or the like during writing, it is necessary that for example, a button or the like provided at the rear end of a lead pipe is knocked to thereby deliver the lead of the desired length.
However, since this lead-feeding operation is not carried out unless the writing operation is discontinued, there gives rise to a problem in that the writing efficiency is deteriorated.